Hate to tell you this, but if your clutch is slipping there is no additive that will help. The ZDDP additive is a high-pressure additive, which helps to protect the cam/rocker arm interface.

Its normal for a clutch to slip when there has been an oil used that has friction modifiers, or cable not adjustsed correctly. Does your clutch lever have free play?

Yes, it sure can,, a cheap, effective oil is Rotella 15w40.

I might lean towards a additive as I brought 4 Litres of oil at $75 and only used half. I see Oldfeller has posted some additive options.

You know Paul, I have a hard time understanding what you are NOT asking.  

You PM me with a question, I answer it.

You post in the main oil thread, I answer it.

I'll answer you again -- please try to read the thread reference given below.   It has mix ratios for Eastwood ZDDP Booster.

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1345080430/0#0


If you need something else, you really need to try to articulate what it is that you really want.

I'm not into guessing, especially not knowing what oil you are really using nor what PPM of ZDDP it already contains.

Listen to Justin and Charon, oil is important, but a slipping clutch can also come from maladjustment and it can result from previous abuse with an energy star compound in a previous crankcase full of oil.

ZDDP by itself isn't going to stop your clutch from slipping ....

 
Justin, he's keeping multiple theads going (a big no-no around here, BTW) -- he's from New Zealand and he can't find Rotella oil where he lives.

He's buying stuff that he has no clue about how much ZDDP is in it already.

So, we can't really help him very much.

Except to ask how he adjusted his clutch (tell us exactly how you did it, all the steps).

I would suspect his clutch is a) contaminated and b) not adjusted correctly but that would be me ASSuMeing stuff,  now wouldn't it?

The clutch did not slip before, it only does it in 4th and not all the time. in 1st 2nd and 3rd I can give it full throttle and the clutch is fine. So why is the clutch slipping only in top gear, and only when the oil has heated, and not all the time just once in a while.
I reckon its the oil after reading Oldfellers post.
And I apologise for multiple threads, It was not my intention to piss anyone off. I know now how these things work.
As for not knowing about what oil to put in, I was trusting people in the appropriate feild to give me the right product. After telling them what you told me they are happy to refund me. They use it in pre 1989 motorcycles without any problems, but not in a Savage.
Being a member of this site has helped me to learn more about my bike. Now I know a little more about oil. Thanks Oldfeller.